A camera mounted on a smart device like a smartphone has similar performance to a general digital camera, and many people have taken their pictures with their smart device carried always with them, not with a digital camera. Accordingly, a consumer's desire to take his or her picture and to instantly print the picture, without any separate conversion, has been gradually increased.
So as to satisfy such consumer's desire, photo printers have been proposed so that pictures on smartphones can be instantly printed whenever and wherever.
There are various kinds of photo printers, but among them, particularly, a photo printer is proposed wherein printing paper to which a zero-ink printing technology is adopted is used, thereby requiring no ink or cartridge to reduce the maintenance cost thereof. In case of such zero-ink printing technology, the part corresponding to the cartridge is contained in the paper, and accordingly, only heat is used to express colors. That is, dyes, which respond to heat and thus express colors, are laminated on the paper, so that the heating temperature or heating time of a head is controlled to print images (pictures) or texts.
Referring to FIGS. 1 to 3, a conventional photo printer 100 includes a base 110, a pickup roller R1, a platen roller R2, a head 140, swing brackets 150, and pressurizing means 160.
The base 110 has a paper feeding part 111 disposed thereon to stackedly accommodate paper sheets therein and a lower base 115 extended forward from the underside thereof.
The pickup roller R1 protrudes from the bottom surface of the paper feeding part 111 of the base 110 to forward feed the paper located at the lowermost position among the stacked paper.
The platen roller R2 is adapted to discharge the paper fed by the pickup roller R1 forward and has a rotary shaft coupled to the lower base 115.
The head 140 is disposed above the platen roller R2 and is adapted to apply given heat to the paper to express colors corresponding to the given heat, thereby printing images or texts. Further, a ceramic plate (not shown) is disposed on top of the head 140, and a heat radiating plate 141, which is made of a metal material, is placed on top of the ceramic plate.
Further, a PCB 142 is provided to control a heating temperature and heating time of the head 140. That is, the head 140 and the PCB 142 are attached to the underside of the heat radiating plate 141.
The paper enters a space between the head 140 and the platen roller R2, and according to the present invention, especially, the head 140 is rotatably mounted onto the base 110. In detail, the head 140 is coupled to a mounting part 151 disposed on the front sides of the swing brackets 150.
So as to allow the space between the head 140 and the platen roller R2 to be widened at the time when the paper enters the space between the head 140 and the platen roller R2, further, hinge holes 152 are formed on the rear sides of the swing brackets 150 in such a manner as to be coupled to rotary shafts 113 disposed on the side walls of the base 110.
Furthermore, the head 140 comes into close contact with the paper to apply the heat to the paper, and so as to allow the head 140 to come into close contact with the paper, the pressurizing means 160 is provided to pressurize the head 140 downward. The pressurizing means 160 includes a pressurizing part 161 for pressurizing top of the head 140 and hinge holes 162 for rotating the pressurizing part 161 coaxially with respect to the rotary shaft 113.
Even though the top of the head 140 is pressurized against the pressurizing means 160, locking projections 153 of the swing brackets 150 are locked onto stoppers 115a formed on both sides of the base 110, and accordingly, they are not descended anymore, so that the head 140 does not come into contact with the platen roller R2, thereby forming a gap from the platen roller R2.
Under the configuration of the conventional photo printer, like this, the formation of the gap between the head 140 and the platen roller R2 at the time when the head 140 is coupled is achieved by means of the locking projections 153 and the stoppers 115a, which undesirably causes the gap to be not maintained constantly. In more detail, gaps on both sides of the head 140 may be different from each other due to mechanical errors of the locking projections 153 and the stoppers 115a, and further, gaps after assembled may be different from set gaps.
[National Research and Development Program Supporting the Invention] Industrial Technology Innovation Program
[Project No.] 10080144
[Ministry Name] Ministry of Trade, Industry and Energy
[Research Management Agency] Korea Evaluation Institute of Industrial Technology
[Research Project Name] Material Component Technology Development Project (Investor-linked type Technology Development Project)
[Research Project Name] Development of ultra slim engine for zero ink type mobile printer
[Contribution Rate] 1/5
[Host Institution] DS Global Co., Ltd
[Period of Time for Research] Aug. 1, 2017 to Dec. 31, 2019